Electrochemical Performance Analysis of Heteroatom Modified Porous Iron, Cobalt-Nitrogen-Carbon Based Electrocatalyst toward Oxygen Reduction Reaction

The drawback of commercial Pt-based electrocatalysts, such as poor stability and high cost, is one of the major issues which limits the promotion of fuel cells and related green energy application. Therefore, developing the inexpensive alternative electrocatalysts for high-performance and stable oxygen reduction reaction (ORR) has become a research hotspot in the field of electrocatalysis. Herein, a series of heteroatom modified porous iron, cobalt-nitrogen-carbon based electrocatalysts were successfully fabricated by modifying the FeCo/NC by additional introduction of heteroatoms (B, P and F) in this work. The mechanism of ORR performance boosted by introduction of B, P and F was explored by combining well characterization of composition and morphology with rational electrochemical tests. The as-fabricated FeCo/NFC sample exhibited highly efficient ORR activity with the half-wave potential of 0.84 V, electron transfer number of 3.85 and HO2- yield of 7.61% at 0.5 V, which was comparable to those of commercial Pt/C. Meanwhile, the FeCo/NFC also displayed outstanding stability and methanol tolerance in alkaline electrolyte which demonstrated excellent application potential in the field of fuel cells as an alternative electrocatalyst for commercial Pt/C.